# Source code for ubelt.util_repr

    """
    Defines the function :func:`urepr`, which allows for a bit more customization
    than :func:`repr` or :func:`pprint.pformat`. See the docstring for more details.

    Two main goals of urepr are to provide nice string representations of nested
    data structures and make those "eval-able" whenever possible. As an example
    take the value ``float('inf')``, which normally has a non-evalable repr of
    ``inf``:

    >>> import ubelt as ub
    >>> ub.urepr(float('inf'))
    "float('inf')"

    The ``newline`` (or ``nl``) keyword argument can control how deep in the
    nesting newlines are allowed.

    >>> print(ub.urepr({1: float('nan'), 2: float('inf'), 3: 3.0}))
    {
        1: float('nan'),
        2: float('inf'),
        3: 3.0,
    }

    >>> print(ub.urepr({1: float('nan'), 2: float('inf'), 3: 3.0}, nl=0))
    {1: float('nan'), 2: float('inf'), 3: 3.0}

    You can also define or overwrite how representations for different types are
    created. You can either create your own extension object, or you can
    monkey-patch ``ub.util_repr._REPR_EXTENSIONS`` without specifying the
    extensions keyword argument (although this will be a global change).

    >>> import ubelt as ub
    >>> extensions = ub.util_repr.ReprExtensions()
    >>> @extensions.register(float)
    >>> def my_float_formater(data, **kw):
    >>>     return "monkey({})".format(data)
    >>> print(ub.urepr({1: float('nan'), 2: float('inf'), 3: 3.0}, nl=0, extensions=extensions))
    {1: monkey(nan), 2: monkey(inf), 3: monkey(3.0)}

    As of ubelt 1.1.0 you can now access and update the default extensions via the
    ``EXTENSIONS`` attribute of the :func:`urepr` function itself.

    >>> # xdoctest: +SKIP
    >>> # We skip this at test time to not modify global state
    >>> import ubelt as ub
    >>> @ub.urepr.EXTENSIONS.register(float)
    >>> def my_float_formater(data, **kw):
    >>>     return "monkey2({})".format(data)
    >>> print(ub.urepr({1: float('nan'), 2: float('inf'), 3: 3.0}, nl=0))
    """
    import collections
    from ubelt import util_str
    from ubelt import util_list

    __all__ = ['urepr', 'ReprExtensions']

    def urepr(data, **kwargs):
        """
        Makes a pretty string representation of ``data``.

        Makes a pretty and easy-to-doctest string representation. Has nice handling
        of common nested datatypes. This is an alternative to repr, and
        :func:`pprint.pformat`.

        This output of this function are configurable. By default it aims to
        produce strings that are consistent, compact, and executable.  This makes
        them great for doctests.

        Note:
            This function has many keyword arguments that can be used to customize
            the final representation. For convenience some of the more frequently
            used kwargs have short aliases. See "Kwargs" for more details.

        Note:
            For large data items, this can be noticeably slower than pprint.pformat
            and much slower than the builtin repr. Benchmarks exist in the repo
            under dev/bench/bench_urepr_vs_alternatives.py

        Args:
            data (object):
                an arbitrary python object to form the string "representation" of

        Kwargs:
            si, stritems, (bool):
                dict/list items use str instead of repr

            strkeys, sk (bool):
                dict keys use str instead of repr

            strvals, sv (bool):
                dict values use str instead of repr

            nl, newlines (int | bool):
                number of top level nestings to place a newline after. If true all
                items are followed by newlines regardless of nesting level.
                Defaults to 1 for lists and True for dicts.

            nobr, nobraces (bool):
                if True, text will not contain outer braces for containers.
                Defaults to False.

            cbr, compact_brace (bool):
                if True, braces are compactified (i.e. they will not have newlines
                placed directly after them, think java / K&R / 1TBS).
                Defaults to False.

            trailsep, trailing_sep (bool):
                if True, a separator is placed after the last item in a sequence.
                By default this is True if there are any ``nl > 0``.

            explicit (bool):
                changes dict representation from ``{k1: v1, ...}`` to
                ``dict(k1=v1, ...)``.  Defaults to False.

                Modifies:
                    default kvsep is modified to  ``'='``
                    dict braces from `{}` to `dict()`.

            compact (bool):
                Produces values more suitable for space constrianed environments
                Defaults to False.

                Modifies:
                    default kvsep is modified to ``'='``
                    default itemsep is modified to  ``''``
                    default nobraces is modified to ``1``.
                    default newlines is modified to ``0``.
                    default strkeys to ``True``
                    default strvals to ``True``

            precision (int | None):
                if specified floats are formatted with this precision.
                Defaults to None

            kvsep (str):
                separator between keys and values. Defaults to ': '

            itemsep (str):
                separator between items. This separator is placed after commas,
                which are currently not configurable. This may be modified in the
                future. Defaults to ' '.

            sort (bool | callable | None):
                if 'auto', then sort unordered collections, but keep the ordering
                of ordered collections. This option attempts to be deterministic in
                most cases. Defaults to None.

                if True, then ALL collections will be sorted in the returned text.

            suppress_small (bool):
                passed to :func:`numpy.array2string` for ndarrays

            max_line_width (int):
                passed to :func:`numpy.array2string` for ndarrays

            with_dtype (bool):
                only relevant to numpy.ndarrays. if True includes the dtype.
                Defaults to `not strvals`.

            align (bool | str):
                if True, will align multi-line dictionaries by the kvsep.
                Defaults to False.

            extensions (ReprExtensions):
                a custom :class:`ReprExtensions` instance that can overwrite
                or define how different types of objects are formatted.

        Returns:
            str: outstr - output string

        Note:
            There are also internal kwargs, which should not be used:

                _return_info (bool):  return information about child context

                _root_info (depth): information about parent context

        RelatedWork:
            :func:`rich.pretty.pretty_repr`
            :func:`pprint.pformat`

        Example:
            >>> import ubelt as ub
            >>> dict_ = {
            ...     'custom_types': [slice(0, 1, None), 1/3],
            ...     'nest_dict': {'k1': [1, 2, {3: {4, 5}}],
            ...                   'key2': [1, 2, {3: {4, 5}}],
            ...                   'key3': [1, 2, {3: {4, 5}}],
            ...                   },
            ...     'nest_dict2': {'k': [1, 2, {3: {4, 5}}]},
            ...     'nested_tuples': [tuple([1]), tuple([2, 3]), frozenset([4, 5, 6])],
            ...     'one_tup': tuple([1]),
            ...     'simple_dict': {'spam': 'eggs', 'ham': 'jam'},
            ...     'simple_list': [1, 2, 'red', 'blue'],
            ...     'odict': ub.odict([(2, '1'), (1, '2')]),
            ... }
            >>> # In the interest of saving space we are only going to show the
            >>> # output for the first example.
            >>> result = ub.urepr(dict_, nl=1, precision=2)
            >>> import pytest
            >>> import sys
            >>> if sys.version_info[0:2] <= (3, 6):
            >>>     # dictionary order is not guaranteed in 3.6 use repr2 instead
            >>>     pytest.skip()
            >>> print(result)
            {
                'custom_types': [slice(0, 1, None), 0.33],
                'nest_dict': {'k1': [1, 2, {3: {4, 5}}], 'key2': [1, 2, {3: {4, 5}}], 'key3': [1, 2, {3: {4, 5}}]},
                'nest_dict2': {'k': [1, 2, {3: {4, 5}}]},
                'nested_tuples': [(1,), (2, 3), {4, 5, 6}],
                'one_tup': (1,),
                'simple_dict': {'spam': 'eggs', 'ham': 'jam'},
                'simple_list': [1, 2, 'red', 'blue'],
                'odict': {2: '1', 1: '2'},
            }
            >>> # You can try the rest yourself.
            >>> result = ub.urepr(dict_, nl=3, precision=2); print(result)
            >>> result = ub.urepr(dict_, nl=2, precision=2); print(result)
            >>> result = ub.urepr(dict_, nl=1, precision=2, itemsep='', explicit=True); print(result)
            >>> result = ub.urepr(dict_, nl=1, precision=2, nobr=1, itemsep='', explicit=True); print(result)
            >>> result = ub.urepr(dict_, nl=3, precision=2, cbr=True); print(result)
            >>> result = ub.urepr(dict_, nl=3, precision=2, si=True); print(result)
            >>> result = ub.urepr(dict_, nl=3, sort=True); print(result)
            >>> result = ub.urepr(dict_, nl=3, sort=False, trailing_sep=False); print(result)
            >>> result = ub.urepr(dict_, nl=3, sort=False, trailing_sep=False, nobr=True); print(result)

        Example:
            >>> import ubelt as ub
            >>> def _nest(d, w):
            ...     if d == 0:
            ...         return {}
            ...     else:
            ...         return {'n{}'.format(d): _nest(d - 1, w + 1), 'm{}'.format(d): _nest(d - 1, w + 1)}
            >>> dict_ = _nest(d=4, w=1)
            >>> result = ub.urepr(dict_, nl=6, precision=2, cbr=1)
            >>> print('---')
            >>> print(result)
            >>> result = ub.urepr(dict_, nl=-1, precision=2)
            >>> print('---')
            >>> print(result)

        Example:
            >>> import ubelt as ub
            >>> data = {'a': 100, 'b': [1, '2', 3], 'c': {20:30, 40: 'five'}}
            >>> print(ub.urepr(data, nl=1))
            {
                'a': 100,
                'b': [1, '2', 3],
                'c': {20: 30, 40: 'five'},
            }
            >>> # Compact is useful for things like timerit.Timerit labels
            >>> print(ub.urepr(data, compact=True))
            a=100,b=[1,2,3],c={20=30,40=five}
            >>> print(ub.urepr(data, compact=True, nobr=False))
            {a=100,b=[1,2,3],c={20=30,40=five}}
        """
        custom_extensions = kwargs.get('extensions', None)

        _return_info = kwargs.get('_return_info', False)
        kwargs['_root_info'] = _rectify_root_info(kwargs.get('_root_info', None))

        if kwargs.get('compact', False):
            # Compact profile defaults
            kwargs['newlines'] = kwargs.get('newlines', 0)
            kwargs['strkeys'] = kwargs.get('strkeys', True)
            kwargs['strvals'] = kwargs.get('strvals', True)
            kwargs['nobraces'] = kwargs.get('nobraces', 1)
            kwargs['itemsep'] = kwargs.get('itemsep', '')
            kwargs['kvsep'] = kwargs.get('kvsep', '=')

        outstr = None
        _leaf_info = None

        if custom_extensions:
            func = custom_extensions.lookup(data)
            if func is not None:
                outstr = func(data, **kwargs)

        if outstr is None:
            if isinstance(data, dict):
                outstr, _leaf_info = _format_dict(data, **kwargs)
            elif isinstance(data, (list, tuple, set, frozenset)):
                outstr, _leaf_info = _format_list(data, **kwargs)

        if outstr is None:
            # check any globally registered functions for special formatters
            func = _REPR_EXTENSIONS.lookup(data)
            if func is not None:
                outstr = func(data, **kwargs)
            else:
                outstr = _format_object(data, **kwargs)

        if _return_info:
            _leaf_info = _rectify_leaf_info(_leaf_info)
            return outstr, _leaf_info
        else:
            return outstr

    def _rectify_root_info(_root_info):
        if _root_info is None:
            _root_info = {
                'depth': 0,
            }
        return _root_info

    def _rectify_leaf_info(_leaf_info):
        if _leaf_info is None:
            _leaf_info = {
                'max_height': 0,
                'min_height': 0,
            }
        return _leaf_info

    class ReprExtensions:
        """
        Helper class for managing non-builtin (e.g. numpy) format types.

        This module (:mod:`ubelt.util_repr`) maintains a global set of basic
        extensions, but it is also possible to create a locally scoped set of
        extensions and explicitly pass it to urepr. The following example
        demonstrates this.

        Example:
            >>> import ubelt as ub
            >>> class MyObject:
            >>>     pass
            >>> data = {'a': [1, 2.2222, MyObject()], 'b': MyObject()}
            >>> # Create a custom set of extensions
            >>> extensions = ub.ReprExtensions()
            >>> # Register a function to format your specific type
            >>> @extensions.register(MyObject)
            >>> def format_myobject(data, **kwargs):
            >>>     return 'I can do anything here'
            >>> # Repr2 will now respect the passed custom extensions
            >>> # Note that the global extensions will still be respected
            >>> # unless they are overloaded.
            >>> print(ub.urepr(data, nl=-1, precision=1, extensions=extensions))
            {
                'a': [1, 2.2, I can do anything here],
                'b': I can do anything here
            }
            >>> # Overload the formatter for float and int
            >>> @extensions.register((float, int))
            >>> def format_myobject(data, **kwargs):
            >>>     return str((data + 10) // 2)
            >>> print(ub.urepr(data, nl=-1, precision=1, extensions=extensions))
            {
                'a': [5, 6.0, I can do anything here],
                'b': I can do anything here
            }
        """
        # set_types = [set, frozenset]
        # list_types = [list, tuple]
        # dict_types = [dict]
        # custom_types = {
        #     'numpy': [],
        #     'pandas': [],
        # }
        # @classmethod
        # def sequence_types(cls):
        #     return cls.list_types + cls.set_types

        def __init__(self):
            self._type_registry = {}      # type: Dict[Type, Callable]  # NOQA
            self._typename_registry = {}  # type: Dict[str, Callable]  # NOQA
            self._lazy_queue = []         # type: List[Callable]  # NOQA
            # self._lazy_registrations = [
            #     self._register_numpy_extensions,
            #     self._register_builtin_extensions,
            # ]

        def register(self, key):
            """
            Registers a custom formatting function with ub.urepr

            Args:
                key (Type | Tuple[Type] | str): indicator of the type

            Returns:
                Callable: decorator function
            """
            def _decorator(func):
                if isinstance(key, tuple):
                    for t in key:
                        self._type_registry[t] = func
                if isinstance(key, str):
                    self._typename_registry[key] = func
                else:
                    self._type_registry[key] = func
                return func
            return _decorator

        def lookup(self, data):
            """
            Returns an appropriate function to format ``data`` if one has been
            registered.

            Args:
                data (Any): an instance that may have a registered formatter

            Returns:
                Callable: the formatter for the given type
            """
            # Evaluate the lazy queue if anything is in it
            if self._lazy_queue:
                for func in self._lazy_queue:
                    func()
                self._lazy_queue = []

            for type_, func in self._type_registry.items():
                if isinstance(data, type_):
                    return func

            # Fallback to registered typenames.
            # If we cannot find a formatter for this type, then return None
            typename = type(data).__name__
            func = self._typename_registry.get(typename, None)
            return func

        def _register_pandas_extensions(self):
            """
            Example:
                >>> # xdoctest: +REQUIRES(module:pandas)
                >>> # xdoctest: +IGNORE_WHITESPACE
                >>> import pandas as pd
                >>> import numpy as np
                >>> import ubelt as ub
                >>> rng = np.random.RandomState(0)
                >>> data = pd.DataFrame(rng.rand(3, 3))
                >>> print(ub.urepr(data))
                >>> print(ub.urepr(data, precision=2))
                >>> print(ub.urepr({'akeyfdfj': data}, precision=2))
            """
            @self.register('DataFrame')
            def format_pandas(data, **kwargs):  # nocover
                precision = kwargs.get('precision', None)
                float_format = (None if precision is None
                                else '%.{}f'.format(precision))
                formatted = data.to_string(float_format=float_format)
                return formatted

        # def _register_torch_extensions(self):
        #     @self.register('Tensor')
        #     def format_tensor(data, **kwargs):
        #         """
        #         Example:
        #             >>> # xdoctest: +REQUIRES(module:torch)
        #             >>> # xdoctest: +IGNORE_WHITESPACE
        #             >>> import torch
        #             >>> import numpy as np
        #             >>> data = np.array([[.2, 42, 5], [21.2, 3, .4]])
        #             >>> data = torch.from_numpy(data)
        #             >>> data = torch.rand(100, 100)
        #             >>> print('data = {}'.format(ub.urepr(data, nl=1)))
        #             >>> print(ub.urepr(data))

        #         """
        #         import numpy as np
        #         func = self._type_registry[np.ndarray]
        #         npdata = data.data.cpu().numpy()
        #         # kwargs['strvals'] = True
        #         kwargs['with_dtype'] = False
        #         formatted = func(npdata, **kwargs)
        #         # hack for prefix class
        #         formatted = formatted.replace('np.array', '__Tensor')
        #         # import ubelt as ub
        #         # formatted = ub.hzcat('Tensor(' + formatted + ')')
        #         return formatted

        def _register_numpy_extensions(self):
            """
            Example:
                >>> # xdoctest: +REQUIRES(module:numpy)
                >>> import sys
                >>> import pytest
                >>> import ubelt as ub
                >>> if not ub.modname_to_modpath('numpy'):
                ...     raise pytest.skip()
                >>> # xdoctest: +IGNORE_WHITESPACE
                >>> import numpy as np
                >>> data = np.array([[.2, 42, 5], [21.2, 3, .4]])
                >>> print(ub.urepr(data))
                np.array([[ 0.2, 42. ,  5. ],
                          [21.2,  3. ,  0.4]], dtype=np.float64)
                >>> print(ub.urepr(data, with_dtype=False))
                np.array([[ 0.2, 42. ,  5. ],
                          [21.2,  3. ,  0.4]])
                >>> print(ub.urepr(data, strvals=True))
                [[ 0.2, 42. ,  5. ],
                 [21.2,  3. ,  0.4]]
                >>> data = np.empty((0, 10), dtype=np.float64)
                >>> print(ub.urepr(data, strvals=False))
                np.empty((0, 10), dtype=np.float64)
                >>> print(ub.urepr(data, strvals=True))
                []
                >>> data = np.ma.empty((0, 10), dtype=np.float64)
                >>> print(ub.urepr(data, strvals=False))
                np.ma.empty((0, 10), dtype=np.float64)
            """

            # TODO: should we register numpy using the new string method?
            import numpy as np
            @self.register(np.ndarray)
            def format_ndarray(data, **kwargs):
                import re
                strvals = kwargs.get('sv', kwargs.get('strvals', False))
                itemsep = kwargs.get('itemsep', ' ')
                precision = kwargs.get('precision', None)
                suppress_small = kwargs.get('supress_small', None)
                max_line_width = kwargs.get('max_line_width', None)
                with_dtype = kwargs.get('with_dtype', kwargs.get('dtype', not strvals))
                newlines = kwargs.pop('nl', kwargs.pop('newlines', 1))

                # if with_dtype and strvals:
                #     raise ValueError('cannot format with strvals and dtype')

                separator = ',' + itemsep

                if strvals:
                    prefix = ''
                    suffix = ''
                else:
                    modname = type(data).__module__
                    # substitute shorthand for numpy module names
                    np_nice = 'np'
                    modname = re.sub('\\bnumpy\\b', np_nice, modname)
                    modname = re.sub('\\bma.core\\b', 'ma', modname)

                    class_name = type(data).__name__
                    if class_name == 'ndarray':
                        class_name = 'array'

                    prefix = modname + '.' + class_name + '('

                    if with_dtype:
                        dtype_repr = data.dtype.name
                        # dtype_repr = np.core.arrayprint.dtype_short_repr(data.dtype)
                        suffix = ',{}dtype={}.{})'.format(itemsep, np_nice, dtype_repr)
                    else:
                        suffix = ')'

                if not strvals and data.size == 0 and data.shape != (0,):
                    # Special case for displaying empty data
                    prefix = modname + '.empty('
                    body = repr(tuple(map(int, data.shape)))
                else:
                    body = np.array2string(data, precision=precision,
                                           separator=separator,
                                           suppress_small=suppress_small,
                                           prefix=prefix,
                                           max_line_width=max_line_width)

                if not strvals:
                    # Handle special float values inf / nan
                    body = re.sub('\\binf\\b', np_nice + '.inf', body)
                    body = re.sub('\\bnan\\b', np_nice + '.nan', body)

                if not newlines:
                    # remove newlines if we need to
                    body = re.sub('\n *', '', body)
                formatted = prefix + body + suffix
                return formatted

            # Hack, make sure we also register numpy floats
            self.register(np.float32)(self._type_registry[float])

        def _register_builtin_extensions(self):
            @self.register(float)
            def format_float(data, **kwargs):
                precision = kwargs.get('precision', None)
                strvals = kwargs.get('sv', kwargs.get('strvals', False))

                if precision is None:
                    text = str(data)
                else:
                    text = ('{:.%df}' % precision).format(data)

                if not strvals:
                    # Ensure the representation of inf and nan is evaluatable
                    # NOTE: sometimes this function is used to make json objects
                    # how can we ensure that this doesn't break things?
                    # Turns out json, never handled these cases. In the future we
                    # may want to add a json flag to urepr to encourage it to
                    # output json-like representations.
                    # json.loads("[0, 1, 2, nan]")
                    # json.loads("[Infinity, NaN]")
                    # json.dumps([float('inf'), float('nan')])
                    import math
                    if math.isinf(data) or math.isnan(data):
                        text = "float('{}')".format(text)

                return text

            @self.register(slice)
            def format_slice(data, **kwargs):
                if kwargs.get('itemsep', ' ') == '':
                    return 'slice(%r,%r,%r)' % (data.start, data.stop, data.step)
                else:
                    return _format_object(data, **kwargs)

    _REPR_EXTENSIONS = ReprExtensions()
    _REPR_EXTENSIONS._register_builtin_extensions()

    def _lazy_init():
        """
        Only called in the case where we encounter an unknown type that a commonly
        used external library might have. For now this is just numpy. Numpy is
        ubiquitous.
        """
        try:
            # TODO: can we use lazy loading to prevent trying to import numpy until
            # some attribute of _REPR_EXTENSIONS is used?
            _REPR_EXTENSIONS._register_numpy_extensions()
            _REPR_EXTENSIONS._register_pandas_extensions()
            # _REPR_EXTENSIONS._register_torch_extensions()
        except ImportError:  # nocover
            pass

    _REPR_EXTENSIONS._lazy_queue.append(_lazy_init)

    def _format_object(val, **kwargs):
        stritems = kwargs.get('si', kwargs.get('stritems', False))
        strvals = stritems or kwargs.get('sv', kwargs.get('strvals', False))
        base_valfunc = str if strvals else repr
        itemstr = base_valfunc(val)
        return itemstr

    def _format_list(list_, **kwargs):
        """
        Makes a pretty printable / human-readable string representation of a
        sequence. In most cases this string could be evaled.

        Args:
            list_ (list): input list
            **kwargs: nl, newlines, packed, nobr, nobraces, itemsep, trailing_sep,
                strvals indent_, precision, use_numpy, with_dtype, force_dtype,
                stritems, strkeys, explicit, sort, key_order, maxlen

        Returns:
            Tuple[str, Dict] : retstr, _leaf_info

        Example:
            >>> print(_format_list([])[0])
            []
            >>> print(_format_list([], nobr=True)[0])
            []
            >>> print(_format_list([1], nl=0)[0])
            [1]
            >>> print(_format_list([1], nobr=True)[0])
            1,
        """
        kwargs['_root_info'] = _rectify_root_info(kwargs.get('_root_info', None))
        kwargs['_root_info']['depth'] += 1

        newlines = kwargs.pop('nl', kwargs.pop('newlines', 1))
        kwargs['nl'] = _rectify_countdown_or_bool(newlines)

        nobraces = kwargs.pop('nobr', kwargs.pop('nobraces', False))
        kwargs['nobraces'] = _rectify_countdown_or_bool(nobraces)

        itemsep = kwargs.get('itemsep', ' ')

        compact_brace = kwargs.get('cbr', kwargs.get('compact_brace', False))
        # kwargs['cbr'] = _rectify_countdown_or_bool(compact_brace)

        itemstrs, _leaf_info = _list_itemstrs(list_, **kwargs)
        if len(itemstrs) == 0:
            nobraces = False  # force braces to prevent empty output

        is_tuple = isinstance(list_, tuple)
        is_set = isinstance(list_, (set, frozenset,))
        if nobraces:
            lbr, rbr = '', ''
        elif is_tuple:
            lbr, rbr  = '(', ')'
        elif is_set:
            lbr, rbr  = '{', '}'
        else:
            lbr, rbr  = '[', ']'

        # Doesn't actually put in trailing comma if on same line
        trailing_sep = kwargs.get('trailsep', kwargs.get('trailing_sep', newlines > 0 and len(itemstrs)))

        # The trailing separator is always needed for single item tuples
        if is_tuple and len(list_) <= 1:
            trailing_sep = True

        if len(itemstrs) == 0:
            newlines = False

        retstr = _join_itemstrs(itemstrs, itemsep, newlines, _leaf_info, nobraces,
                                trailing_sep, compact_brace, lbr, rbr)
        return retstr, _leaf_info

    def _format_dict(dict_, **kwargs):
        """
        Makes a pretty printable / human-readable string representation of a
        dictionary. In most cases this string could be evaled.

        Args:
            dict_ (dict):  a dictionary
            **kwargs: si, stritems, strkeys, strvals, sk, sv, nl, newlines, nobr,
                      nobraces, cbr, compact_brace, trailing_sep,
                      explicit, itemsep, precision, kvsep, sort

        Kwargs:
            sort (None):
                if True, sorts ALL collections and subcollections,
                note, collections with undefined orders (e.g. dicts, sets) are
                sorted by default. Defaults to None.

            nl (int | None):
                preferred alias for newline. can be a countdown variable.
                Defaults to None.

            explicit (int | bool):
                can be a countdown variable.
                if True, uses dict(a=b) syntax instead of {'a': b}.
                Defaults to False.

            nobr (bool): removes outer braces. Defaults to False.

        Returns:
            Tuple[str, Dict] : retstr, _leaf_info

        Example:
            >>> from ubelt.util_repr import *  # NOQA
            >>> dict_ = {'a': 'edf', 'bc': 'ghi'}
            >>> print(_format_dict(dict_)[0])
            {
                'a': 'edf',
                'bc': 'ghi',
            }
            >>> print(_format_dict(dict_, align=True)[0])
            >>> print(_format_dict(dict_, align=':')[0])
            {
                'a' : 'edf',
                'bc': 'ghi',
            }
            >>> print(_format_dict(dict_, explicit=True, align=True)[0])
            dict(
                a ='edf',
                bc='ghi',
            )
        """
        kwargs['_root_info'] = _rectify_root_info(kwargs.get('_root_info', None))
        kwargs['_root_info']['depth'] += 1

        stritems = kwargs.pop('si', kwargs.pop('stritems', False))
        if stritems:
            kwargs['strkeys'] = True
            kwargs['strvals'] = True

        kwargs['strkeys'] = kwargs.pop('sk', kwargs.pop('strkeys', False))
        kwargs['strvals'] = kwargs.pop('sv', kwargs.pop('strvals', False))

        newlines = kwargs.pop('nl', kwargs.pop('newlines', True))
        kwargs['nl'] = _rectify_countdown_or_bool(newlines)

        nobraces = kwargs.pop('nobr', kwargs.pop('nobraces', False))
        kwargs['nobraces'] = _rectify_countdown_or_bool(nobraces)

        compact_brace = kwargs.get('cbr', kwargs.get('compact_brace', False))
        # kwargs['cbr'] = _rectify_countdown_or_bool(compact_brace)

        # Doesn't actually put in trailing comma if on same line
        trailing_sep = kwargs.get('trailsep', kwargs.get('trailing_sep', newlines > 0))
        explicit = kwargs.get('explicit', False)
        itemsep = kwargs.get('itemsep', ' ')

        align = kwargs.get('align', False)
        if align and not isinstance(align, str):
            default_kvsep = ': '
            if explicit:
                default_kvsep = '='
            kvsep = kwargs.get('kvsep', default_kvsep)
            align = kvsep

        if len(dict_) == 0:
            retstr = 'dict()' if explicit else '{}'
            _leaf_info = None
        else:
            itemstrs, _leaf_info = _dict_itemstrs(dict_, **kwargs)
            if nobraces:
                lbr, rbr = '', ''
            elif explicit:
                lbr, rbr = 'dict(', ')'
            else:
                lbr, rbr = '{', '}'
            retstr = _join_itemstrs(itemstrs, itemsep, newlines, _leaf_info, nobraces,
                                    trailing_sep, compact_brace, lbr, rbr, align)
        return retstr, _leaf_info

    def _join_itemstrs(itemstrs, itemsep, newlines, _leaf_info, nobraces,
                       trailing_sep, compact_brace, lbr, rbr, align=False):
        """
        Joins string-ified items with separators newlines and container-braces.
        """
        # positive newlines means start counting from the root
        use_newline = newlines > 0

        # negative countdown values mean start counting from the leafs
        # if compact_brace < 0:
        #     compact_brace = (-compact_brace) >= _leaf_info['max_height']
        if newlines < 0:
            use_newline = (-newlines) < _leaf_info['max_height']

        if use_newline:
            sep = ',\n'
            if nobraces:
                if align:
                    itemstrs = _align_lines(itemstrs, character=align)
                body_str = sep.join(itemstrs)
                if trailing_sep and len(itemstrs) > 0:
                    body_str += ','
                retstr = body_str
            else:
                if compact_brace:
                    # Why must we modify the indentation below and not here?
                    # prefix = ''
                    # rest = [util_str.indent(s, prefix) for s in itemstrs[1:]]
                    # indented = itemstrs[0:1] + rest
                    indented = itemstrs
                else:
                    prefix = ' ' * 4
                    indented = [util_str.indent(s, prefix) for s in itemstrs]

                if align:
                    indented = _align_lines(indented, character=align)

                body_str = sep.join(indented)
                if trailing_sep and len(itemstrs) > 0:
                    body_str += ','
                if compact_brace:
                    # Why can we modify the indentation here but not above?
                    braced_body_str = (lbr + body_str.replace('\n', '\n ') + rbr)
                else:
                    braced_body_str = (lbr + '\n' + body_str + '\n' + rbr)
                retstr = braced_body_str
        else:
            sep = ',' + itemsep
            body_str = sep.join(itemstrs)
            if trailing_sep and len(itemstrs) > 0:
                body_str += ','
            retstr  = (lbr + body_str +  rbr)
        return retstr

    def _dict_itemstrs(dict_, **kwargs):
        """
        Create a string representation for each item in a dict.

        Args:
            dict_ (dict): the dict
            **kwargs: explicit, precision, kvsep, strkeys, _return_info, cbr,
                compact_brace, sort

        Example:
            >>> from ubelt.util_repr import *
            >>> dict_ =  {'b': .1, 'l': 'st', 'g': 1.0, 's': 10, 'm': 0.9, 'w': .5}
            >>> kwargs = {'strkeys': True, 'sort': True}
            >>> itemstrs, _ = _dict_itemstrs(dict_, **kwargs)
            >>> char_order = [p[0] for p in itemstrs]
            >>> assert char_order == ['b', 'g', 'l', 'm', 's', 'w']
        """
        import ubelt as ub
        explicit = kwargs.get('explicit', False)
        kwargs['explicit'] = _rectify_countdown_or_bool(explicit)
        precision = kwargs.get('precision', None)

        default_kvsep = ': '
        default_strkeys = False
        if explicit:
            default_strkeys = True
            default_kvsep = '='
        kvsep = kwargs.get('kvsep', default_kvsep)

        def make_item_str(key, val):
            if explicit or kwargs.get('strkeys', default_strkeys):
                key_str = str(key)
            else:
                key_str = urepr(key, precision=precision, newlines=0)

            prefix = key_str + kvsep
            kwargs['_return_info'] = True
            val_str, _leaf_info = urepr(val, **kwargs)

            # If the first line does not end with an open nest char
            # (e.g. for ndarrays), otherwise we need to worry about
            # residual indentation.
            pos = val_str.find('\n')
            first_line = val_str if pos == -1 else val_str[:pos]

            compact_brace = kwargs.get('cbr', kwargs.get('compact_brace', False))

            if compact_brace or not first_line.rstrip().endswith(tuple('([{<')):
                rest = '' if pos == -1 else val_str[pos:]
                # val_str = first_line.lstrip() + rest
                val_str = first_line + rest
                if '\n' in prefix:
                    # Fix issue with keys that span new lines
                    item_str = prefix + val_str
                else:
                    item_str = ub.hzcat([prefix, val_str])
            else:
                item_str = prefix + val_str
            return item_str, _leaf_info

        items = list(dict_.items())
        _tups = [make_item_str(key, val) for (key, val) in items]
        itemstrs = [t[0] for t in _tups]
        max_height = max([t[1]['max_height'] for t in _tups]) if _tups else 0
        _leaf_info = {
            'max_height': max_height + 1,
        }

        sort = kwargs.get('sort', None)
        if sort == 'auto':
            sort = None

        dict_sort_behavior = kwargs.get('_dict_sort_behavior', 'new')
        if dict_sort_behavior == 'old':
            if sort is None:
                # if sort is None, force orderings on unordered collections like dicts,
                # but keep ordering of ordered collections like OrderedDicts.
                # NOTE: WE WANT TO CHANGE THIS TO FALSE BY DEFAULT.
                # MIGHT REQUIRE DEPRECATING PYTHON 3.6 SUPPORT
                sort = True  # LEGACY UBELT BEHAVIOR
                # HOW TO WE INTRODUCE A BACKWARDS COMPATIBLE WAY TO MAKE THIS CHANGE?
                # sort = False  # cannot make this change safely

            if isinstance(dict_, collections.OrderedDict):
                # never sort ordered dicts; they are perfect just the way they are!
                sort = False
        else:
            if sort is None:
                # Dictionaries are sorted by default in 3.7+ so never sort dictionaries
                sort = False

        if sort:
            key = sort if callable(sort) else None
            itemstrs = _sort_itemstrs(items, itemstrs, key)
        return itemstrs, _leaf_info

    def _list_itemstrs(list_, **kwargs):
        """
        Create a string representation for each item in a list.

        Args:
            list_ (Sequence):
            **kwargs: _return_info, sort
        """
        items = list(list_)
        kwargs['_return_info'] = True
        _tups = [urepr(item, **kwargs) for item in items]
        itemstrs = [t[0] for t in _tups]
        max_height = max([t[1]['max_height'] for t in _tups]) if _tups else 0
        _leaf_info = {
            'max_height': max_height + 1,
        }

        sort = kwargs.get('sort', None)
        if sort == 'auto':
            sort = None

        if sort is None:
            # if sort is None, force orderings on unordered collections like sets,
            # but keep ordering of ordered collections like lists.
            sort = isinstance(list_, (set, frozenset))
        if sort:
            key = sort if callable(sort) else None
            itemstrs = _sort_itemstrs(items, itemstrs, key)
        return itemstrs, _leaf_info

    def _sort_itemstrs(items, itemstrs, key=None):
        """
        Equivalent to ``sorted(items)`` except if ``items`` are unorderable, then
        string values are used to define an ordering.
        """
        # First try to sort items by their normal values
        # If that does not work, then sort by their string values
        try:
            # Set ordering is not unique. Sort by strings values instead.
            if len(items) > 0 and isinstance(items[0], (set, frozenset)):
                raise TypeError
            sortx = util_list.argsort(items, key=key)
        except TypeError:
            sortx = util_list.argsort(itemstrs, key=key)
        itemstrs = [itemstrs[x] for x in sortx]
        return itemstrs

    def _rectify_countdown_or_bool(count_or_bool):
        """
        used by recursive functions to specify which level to turn a bool on in
        counting down yields True, True, ..., False
        counting up yields False, False, False, ... True

        Args:
            count_or_bool (bool | int): if positive and an integer, it will count
                down, otherwise it will remain the same.

        Returns:
            int or bool: count_or_bool_

        Example:
            >>> from ubelt.util_repr import _rectify_countdown_or_bool  # NOQA
            >>> count_or_bool = True
            >>> a1 = (_rectify_countdown_or_bool(2))
            >>> a2 = (_rectify_countdown_or_bool(1))
            >>> a3 = (_rectify_countdown_or_bool(0))
            >>> a4 = (_rectify_countdown_or_bool(-1))
            >>> a5 = (_rectify_countdown_or_bool(-2))
            >>> a6 = (_rectify_countdown_or_bool(True))
            >>> a7 = (_rectify_countdown_or_bool(False))
            >>> a8 = (_rectify_countdown_or_bool(None))
            >>> result = [a1, a2, a3, a4, a5, a6, a7, a8]
            >>> print(result)
            [1, 0, 0, -1, -2, True, False, False]
        """
        if count_or_bool is True or count_or_bool is False:
            count_or_bool_ = count_or_bool
        elif isinstance(count_or_bool, int):
            if count_or_bool == 0:
                return 0
            elif count_or_bool > 0:
                count_or_bool_ = count_or_bool - 1
            else:
                # We dont countup negatives anymore
                count_or_bool_ = count_or_bool
        else:
            count_or_bool_ = False
        return count_or_bool_

    def _align_text(text, character='=', replchar=None, pos=0):
        r"""
        Left justifies text on the left side of character

        Args:
            text (str): text to align
            character (str): character to align at
            replchar (str): replacement character (default=None)

        Returns:
            str: new_text

        Example:
            >>> character = '='
            >>> text = 'a = b=\none = two\nthree = fish\n'
            >>> print(text)
            >>> result = (_align_text(text, '='))
            >>> print(result)
            a     = b=
            one   = two
            three = fish
        """
        line_list = text.splitlines()
        new_lines = _align_lines(line_list, character, replchar, pos=pos)
        new_text = '\n'.join(new_lines)
        return new_text

    def _align_lines(line_list, character='=', replchar=None, pos=0):
        r"""
        Left justifies text on the left side of character

        Args:
            line_list (list of strs):
            character (str):
            pos (int or list or None): does one alignment for all chars beyond this
                column position. If pos is None, then all chars are aligned.

        Returns:
            list: new_lines

        Example:
            >>> line_list = 'a = b\none = two\nthree = fish'.split('\n')
            >>> character = '='
            >>> new_lines = _align_lines(line_list, character)
            >>> result = ('\n'.join(new_lines))
            >>> print(result)
            a     = b
            one   = two
            three = fish

        Example:
            >>> line_list = 'foofish:\n    a = b\n    one    = two\n    three    = fish'.split('\n')
            >>> character = '='
            >>> new_lines = _align_lines(line_list, character)
            >>> result = ('\n'.join(new_lines))
            >>> print(result)
            foofish:
                a        = b
                one      = two
                three    = fish

        Example:
            >>> import ubelt as ub
            >>> character = ':'
            >>> text = ub.codeblock('''
                {'max': '1970/01/01 02:30:13',
                 'mean': '1970/01/01 01:10:15',
                 'min': '1970/01/01 00:01:41',
                 'range': '2:28:32',
                 'std': '1:13:57',}''').split('\n')
            >>> new_lines = _align_lines(text, ':', ' :')
            >>> result = '\n'.join(new_lines)
            >>> print(result)
            {'max'   : '1970/01/01 02:30:13',
             'mean'  : '1970/01/01 01:10:15',
             'min'   : '1970/01/01 00:01:41',
             'range' : '2:28:32',
             'std'   : '1:13:57',}

        Example:
            >>> line_list = 'foofish:\n a = b = c\n one = two = three\nthree=4= fish'.split('\n')
            >>> character = '='
            >>> # align the second occurrence of a character
            >>> new_lines = _align_lines(line_list, character, pos=None)
            >>> print(('\n'.join(line_list)))
            >>> result = ('\n'.join(new_lines))
            >>> print(result)
            foofish:
             a   = b   = c
             one = two = three
            three=4    = fish
        """
        import re

        # FIXME: continue to fix ansi
        if pos is None:
            # Align all occurrences
            num_pos = max([line.count(character) for line in line_list])
            pos = list(range(num_pos))

        # Allow multiple alignments
        if isinstance(pos, list):
            pos_list = pos
            # recursive calls
            new_lines = line_list
            for pos in pos_list:
                new_lines = _align_lines(new_lines, character=character,
                                         replchar=replchar, pos=pos)
            return new_lines

        # base case
        if replchar is None:
            replchar = character

        # the pos-th character to align
        lpos = pos
        rpos = lpos + 1

        tup_list = [line.split(character) for line in line_list]

        handle_ansi = True
        if handle_ansi:  # nocover
            # Remove ansi from length calculation
            # References: http://stackoverflow.com/questions/14693701remove-ansi
            ansi_escape = re.compile(r'\x1b[^m]*m')

        # Find how much padding is needed
        maxlen = 0
        for tup in tup_list:
            if len(tup) >= rpos + 1:
                if handle_ansi:  # nocover
                    tup = [ansi_escape.sub('', x) for x in tup]
                left_lenlist = list(map(len, tup[0:rpos]))
                left_len = sum(left_lenlist) + lpos * len(replchar)
                maxlen = max(maxlen, left_len)

        # Pad each line to align the pos-th occurrence of the chosen character
        new_lines = []
        for tup in tup_list:
            if len(tup) >= rpos + 1:
                lhs = character.join(tup[0:rpos])
                rhs = character.join(tup[rpos:])
                # pad the new line with requested justification
                newline = lhs.ljust(maxlen) + replchar + rhs
                new_lines.append(newline)
            else:
                new_lines.append(replchar.join(tup))
        return new_lines

    # Give the urepr function itself a reference to the default extensions
    # register method so the user can modify them without accessing this module
    urepr.extensions = _REPR_EXTENSIONS
    urepr.register = _REPR_EXTENSIONS.register